Reaction product of 2-vinyl-5-norbornene with hexahalocyclopentadienes

ABSTRACT

THE INVENTION IS NEW HALODIMETHANONAPHTHALENES, NAMELY 6-(1&#39;&#39;, 4&#39;&#39;, 5&#39;&#39;, 6&#39;&#39;, 7&#39;&#39;,7&#39;&#39;, - HEXAHALONORBORN-5&#39;&#39;-EN-2&#39;&#39;-YL)1,2,3,4,10,10 - HEXAHALO - 1,4,4A,5,6,7,8,8A, - OCTAHYDRO1,4:5,8 - DIMETHANONAPHALENES, ESPECIALLY 6 - (1&#39;&#39;,4&#39;&#39;, 5&#39;&#39;, 6&#39;&#39;, 7&#39;&#39;, 7&#39;&#39; - HEXACHLORONOBORN - 5&#39;&#39; - EN-2&#39;&#39;-YL)-1,2,3,4,10,10HEXACHLORO - 1,4,4A,5,6,7,6,8,8A - OCTAHYDRO - 1,4:5,8 - DIMETHANONAPHTHALENE (HEREINAFTER &#34;ZOR&#34;), A METHOD OF SYNTHESIZING SAME BY THE REACTION OF 5-VINYL-2-NORBORNENE WITH HEXAHALOCYCLOPENTADIENE, AND USE OF SUCH CHEMICALS FOR FLAMEPROOFING ORGANIC POLYMERIC MATERIALS, ESPECIALLY ABS RESINS TO WHICH THE CHEMICALS IMPART FIRE RESISTANCE WITH UNEXPECTED RETENTION OF DESIRABLE PHYSICAL PROPERTIES.

United States Patent 3,809,725 REACTION PRODUCT 0F Z-VINYL-S-NORBOR-NENE WITH HEXAHALOCYCLOPENTADIENES Richard Waldron Davenport, LincolnPark, N.J., assignor to Uniroyal, Inc., New York, N.Y. No Drawing. FiledApr. 17, 1972, Ser. No. 244,951

. Int. Cl. C07c 23/20, 17/30 US. Cl. 260-648 C 6 Claims ABSTRACT OF THEDISCLOSURE The invention is new halodimethanonaphthalenes, namely6-(1',4',5',6',7',7' hexahalonorborn-5'-en-2'-yl)- 1,2,3,4,10,10hexahalo l,4,4a,5,6,7,8,8a octahydro- .1,4:5,8 dimethanonaphthalenes,especially 6 (1',4',5', 6,7',7 hexachloronorborn 5'en-2'-yl)-1,2,3,4,10,l0- hexachloro 1,4,4a,5,6,7,8,8a octahydro 1,4:5,8dimethanonaphthalene (hereinafter ZOR), a method of synthesizing same bythe reaction of 5-vinyl-2-norbornene with hexahalocyclopentadiene, anduse of such chemicals for flameproofing organic polymeric materials,especially ABS resins to which the chemicals impart fire resistance withunexpected retention of desirable physical properties.

BACKGROUND OF THE DISCLOSURE 1. Field of the invention The field of theinvention is new halodimethanonaphthalenes having the valuable propertyof imparting flame resistance to organic polymeric materials, especiallyABS resins to which they impart fire resistance with unexpectedretention of their desirable physical characteristics, a method ofsynthesizing such chemical compounds, and use thereof for impartingflame resistance to such polymeric materials.

2. Description of the prior art The most pertinent prior art knownconsists of the following U.S. Pats: Reissue 25,430; 3,403,036;3,442,977; and 3,442,980, and British Pat. 1,220,524. US. Reissue 25,430discloses the chemical compound 1,2,3,4,9,9 hexachloro 1,4,4a,5,6,7,8,8aoctahydro 1,4 methanonaphthalene 6,7 dicarboxylic anhydride which issold under the trademark Cloran, while US. 3,442,980 discloses theincorporation of this compound with acrylonitrile-butadiene-styrene(ABS) graft polymers to give flame-retardant compositions. US. 3,442,977shows use of the same compound in conjunction with chlorinatedpolyethylene as a flameproofing adjunct for ABS- graft polymers.

US. 3,403,036 describes a flame retardant for polymeric compositions,having the general formula:

. ds/h X V X where X is selected from the group consisting of bromine,chlorine and fluorine, Y is selected from the group consisting ofbromine, chlorine, fluorine, alkyl and alkoxy; and Z is a tetravalentcyclic hydrocarbon radical containing at least five carbon atoms. Ineach case specified in this patent each reactant forming the Z radicalis characterized by being a cyclic hydrocarbon having two cent'ers ofunsaturation. In contrast, the reactant (5-vinyl-2- norbornene) reactedwith hexahalocyclopentadiene to 3,809,725 Patented May 7., 1974 form theflameproofing compounds of the present invention has only one center ofunsaturation in a cyclic system to which is attached a divalent linearpart. The chemical compounds of the present invention are very difierentfrom any thing taught or suggested by this patent.

British Pat. 1,220,524 describes a flame retardant for polymericcompositions having the general formula:

where X represents a halogen atom; Y and Y represent a halogen atom, analkyl or alkoxy radical containing 1 to 4 carbon atoms; and each of theR radicals, which may be the same or different, represents a hydrogen orhalogen atom or an alkyl radical containing 1 to 4 carbon atoms. Thepreferred structure is given when X, Y, and Y are chlorine and R ishydrogen; for brevity a compound having this preferred structure isreferred to hereinafter as CNB (not a trademark), this being thedesignation under which it is sold. The structure of the compounds ofthe present invention differ in that they have a 5,8-methano group andare therefore 1,4:5,8-dimethanonaphthalenes. The superior flameretarding effectiveness of ZOR, a preferred compound of the presentinvention, compared to CNB is shown in Examples 8 and 11 below.

SUMMARY OF THE INVENTION where X is halogen, preferably chlorine. Whereeach of the Xs is chlorine the compound is identified herein as ZOR,this being a code name used internally by the assignee of thisinvention; it is not a trademark at the present time.

The present invention also provides a method of preparing theabove-identified compounds by heating at 110 C. to 220 C. for 2 to hourstwo or more moles of the hexahalocyclopentadiene and one mole of5-vinyl-2- norbornene. Suitable solvents include xylene,dichilorobenzene, and trichlorobenzene although the reaction may be runin the absence of a solvent. ZOR prepared in this manner is a mixture ofisomers which may be separated by fractional crystallization. Thevariations in melting point of the several mixture forms of ZOR obtainedin preparative Examples 1 through 5 below are attributable to variationsin percentages of the isomers in such mixtures.

The fire retardant additives of this invention may be blended with theABS resin or other polymeric material by conventional techniques such asmilling and compression molding or by injection molding techniques.Theymay material in the amount of from to 35 p.p.h.; preferably from to 30p.p.h. Improved fire retardance can be provided by incorporatingantimony oxide into the fire retardant composition. The amount ofantimony oxide employed can vary widely but typically ranges from 3 to15 p.p.h. The fire retardant ABS compositions made in accordance withthe present invention unexpectedly retain the desirable physicalproperties, particularly impact resistance, hardness, and heatdistortion temperature, and the good processing characteristics of theABS resins.

The expression p.p.h. as used herein means parts by weight of additiveper 100 parts of thermoplastic polymeric material.

ABS resins are the preferred polymeric materials rendered flameretardant by the present invention. The expression ABS resin is usedherein in its ordinary and accepted meaning to designate a thermoplasticresinous acrylonitrile-butadiene-styrene polymeric material, usuallymade b grafting acrylonitrile and styrene monomers onto a rubberypolybutadiene or rubbery butadiene-styrene copolymer spine either by anemulsion polymerization technique or by so-called solutionpolymerization. Fre quently separately prepared styrene-acrylonitrileresinous copolymer is admixed with the product of the grafting step. SeeUS. Pats. 2,820,773; 3,238,275 and 3,624,183 for typical ABS graftcopolymer prepartions. Less commonly, ABS resins are made by blending abutadieneacrylonitrile rubbery copolymer with a styrene-acrylonitrileresinous copolymer.

Less advantageously, organic polymeric materials other than ABS resinscan be rendered flame retardant in accordance with the presentinvention. Examples of such other materials are polyolefins such aspolyethylene and polypropylene, thermoplastic or thermosettingpolyurethanes, polystyrene, thermosetting polyester resins comprising apolyester resin and a copolymerizable monomer such as styrene, etc.

The invention can also be applied to gum plastics other than ABS resinsuch as those made by grafting suitable monomers, such as styrene andacrylonitrile, onto a spine rubber which is a rubbery copolymer ofethylene and propylene (often called EP rubber) or a rubbery terpolymer(generally referred to as an EPDM rubber) of ethylene, propylene and atleast one copolymerizable diene such as 1,4-hexadiene,dicyclopentadiene, cyclooctadiene, methylene norbornene, ethylidenenorbornene, isopropylidene norbornene or mixtures thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preparation of ZOR EXAMPLE 1Preparation of 6-(1,4',5',6',7',7 hexachloronorborn-5- en-2-yl)1,2,3,4,10,10 hexachloro 1,4,4a,5,6,7,8,8aoctahydro-1,4 5,S-dimethanonaphthalene ZOR as made is a mixture of isomers of M.P. 28990and 263-4 and is prepared by causing S-vinyl 2 norbornene to react with2 or more moles of hexachlorocyclopentadiene.

5-vinyl-2-norbornene (30.0 g., 0.25 mole), hexachlorocyclopentadiene(156 g., 0.571 mole, 14.2% excess), and 3,5-di-t-butylcatechol (0.2 g.)were heated and stirred under nitrogen at 180193 C. for 6 hours. Heatingwas then discontinued and methanol (300 ml.) was cautiously addedthrough the reflux condenser with vigorous stirring. After stirring for1 hour, the solid (93%) separated by filtration was washed with methanol(100 ml.). The crude product was purified further by heating and stirredwith methanol (400 ml.) for 1 hour. The hot mixture was filtered toafford ZOR (146 g., 88%, M.P. 202-243 C.). Two isomers, M.P. 289-90" C.and 263-4 C., were separated by fractional crystallization from asolvent consisting of a mixture of chloroform and petroleum ether.

' EXAMPLE Z The experiment of Example 1 was repeated with the exceptionthat the 3,5-di-t-butylcatechol was omitted. The yield of ZOR Was M.P.196222 C.

EXAMPLE 3 The experiment of Example 1 was repeated with the exceptionthat the mixture was heated at C. for 1% hours and then at C. for 16hours. The yield of ZOR Was 88%, M.P. -232 C.

EXAMPLE 4 A mixture of 5-vinyl-2-norbornene (200 g., 1.67 mole),hexachlorocyclopentadiene (950 g., 3.50 mole, 5% excess),3,5-di-t-butylcatechol (1.0 g.) and xylene (1000 ml.) was heated at thereflux temperature for 4 days. The mixture was cooled in an ice bath andthe resulting solid (873 g., 78.7%) was isolated by filtration. Thecrude product was purified further by stirring with petroleum ether(1000 ml.) for 1 hour and filtering to afford ZOR (657 g., 59.2%, M.P.220-254 C.).

EXAMPLE 5 Use of ZOR as a flame retardant The eifectiveness of ZOR as aflame retardant has been established by comparing it with Cloran(trademark) which is widely regarded as one of the more efiective fireretardants for ABS resins. A limited number of comparisons of ZOR withCNB have also been made. In the following examples ZOR will be comparedto Cloran" and CNB to establish that ZOR is a more effective flameretardant and unexpectedly retains the desirable physical .properties ofthe ABS resin.

Fire retardant tests were of three different types: (1) ASTM D-635ahorizontal burning test, (2) ASTM D2863the oxygen index method, and (3)Underwriters Laboratories Subject 94a vertical burning test.

In Examples 6 through 8, 10 and 11, the ABS resin used was a graftcopolymer product containing by weight 19% acrylonitrile, 24% butadieneand 57% styrene. In certain of the examples the legend fSE meansself-extinguishing and the legend NB means that the material tested didnot burn.

EXAMPLE '6 Varying amounts of fire retardant additives were milled intoan ABS resin and compression molded. Fire retardant tests were run bythe ASTM 13-635 and D-2863 methods.

TABLET lASTM :3-635 D-2863 urn re a ox en Code Additlve(s) P.p.h.(in./min.) il r ex A-O None 1.61 18.5 ZOR 15 1. 53 i v 21.0 ZOR, SbiOi15.4 0.85 (2/5 SE) 23.7 OR,SbiOi 15.6 NB 25.4 R, 81310 20.6 NB 28.01Cloran, SbzO 15.4 1.71 22.1 d0 15.6 1.51 23.41 do 20.6 NB 24.7

As shown in Table I, ZOR at the 20 p.p.ln. level with6 p.p.h. ofantimony oxide gives an oxygen index of 2.8.0

ZOR has a significantly higher oxygen index (25.4 vs.

23.4) and superior D-635 performance (non-burning vs. burning at 1.51in./ min.) than a similar Cloran-contain- In order to render ABSselfextinguishing (Group 22.1 p.p.h. of ZOR and 10.3 p.p.h. of antimonyoxide are required. By comparison, 30 p.p.h. of Cloran" and 11 p.p.h. ofantimony oxide are necessary to achieve a slightly inferior rating(Group I). Lowering the amount of ing composition. These resultsindicate thatZOR is su- Cloran results in ABS compositions whicn are nolonger perior to Cloran as a fire retardant for ABS resins. classifidself-extinguishing. Similar results were achieved with NB whereself-extinguishing compositions were EXAMPLE 7 not obtained at the 25.0p.p.h. level with 10.3 p.p.h. of The data of Table II was obtained fromABS resin samantimony oxide. Thus ZOR gives self-extinguishing compleswhich had been compression molded. In each casethe positions by theUL-94 test at lower levels than materials total amount of ZOR andantimony oxide was kept conknown in the art. The notched Izod (14 KT.)impact stant at p.p.h. strength of these self-extinguishing compositions(i.e., 0-5

1 TABLE 11 ABS resin 100 100 100 100 100 100 100 11.36 9.34 7. 92 6. 896.09 5.52 4.94 zon 8.64 10.66 12.08 13.11 13. 91 14. 48 15.06 C1/Sb mtin2:1 3:1 7 4:1 5:1 6:1 7:1 8:1 D-2863 oxygen index 0 5 6 26. 2 25. 6 25.6 24. 8 25. 1 13-635 burnrate (in/min.) 1.07 2 s11, 2 NB 2 SE, 2 NB 4 NB1 SE, 3 NB 2 SE, 2 NB 4 NB Impact (notched izod, R.T. 4")- 2. 72 a. 162.98 3.09 3.50 3.36 2. 9a Rockwell hardness, R 90 a 89 89 89 87 88 88Heat distortion temperature, F 189 85 185 v} 181 185 180 185 As shown inTable II, the oxygen indices of the samples and 'C-7) was approximately4 times higher when ZOR varied only within experimental error over arange of Cl/ rather than Cloran was the flame retardant additive. Sbratio from 3/1 to 8/1. Similarly, D-635 test results showed nosignificant variation since the difference be- EXAMPLE 9 tween SE and NBwas very small in this particularcase. The samples listed in Table Vwere prepared by com- Impact resistance reached a maximum of 3.50 ft.lbs./in. pression molding techniques. at a Cl/Sb ratio of 6/1. The ABScontrol (no additive) TABLE Iv has an impact resistance of 4.30ft.lb./in. Thus the efiect C M of ZOR and antimony oxide upon physicalproperties is omposltmn minimal. Heat distortion and Rockwell hardnessvaried gg 100 1 little over the range studied. These results show thateffec- 'gg 'i tive fire retardation can'be achieved by varying the ratio6 5 of ZOR to antimony oxide over a wide range. pm e fi i Ion 2 Impggtnotlcahe(1181150111111:11. 3. 7 EXAMPLE 8 32:1: di 'sorti (224 p.s.1.annea 176 13 40 UL-94. ,-ie" vertical flame test. SE-O SE-I The testsamples of Table III were prepared as in Ex- Flame 4 7 ample 6. The testmethod was the Underwriters Labora- 1 21.5% acrylonitrile, 21.0%butadiene, 57.5% styrene. tories Subject 94, a vertical burning test. 2Tademark ethylene'bis'steame- These compositions contain suflicient ZORor Cloran and antimony oxide in order to achieve similar performance inthe UL-94 vertical burning test. The composition TABLE III (D-2)containing ZOR has more than twice the impact resistance (3.7 vs. 1.7)of the Cloran-containing commm in position (D-1) and a higher heatdistortion temperature ABS (193 F. vs. 176 F.).

Additive resin Uri-94 (v-1 E MPLE 10 %'i""" 2131i; 2%"8 Z0 a----- i ZOR,shim... 26.9,10.7 SE The samples listed in Table V were prepared by comon, 513283..- 1 gg pression molding techniques. ZOR, b1 ZOR,Sb2Oa 20.9,9.1 B-ND TABLEV c l r ir', 30011.0 SE-I Code E-l 11-2 E-3 11-4 11-5 E-GE-7 io. 24210.5 B-O ABS resin. 100 100 100 100 100 100 100 rr zz g ggg-gqg-g 2 2 I m D 8555 ""51; 15 ""15- ""55 B 2 an 1 sbfloq 4 4 6 6Impact notched ir 11 1 1., 1 41"" 5.2 4.3 2.7 3.0 2.1 2.5 1.0 O0 8 8.1Ratmg Meaning ness, R 91 9s 89 9s 90 SE-O Extinguislfies witfingoseeoudg, GGroup d t fliegltilgxsltgtrgzn SE-I g gs es W11 I1 Sewn n068 u 183 180 180 181 180 180 811-11 Exltinguishgs wlthirt 30 seconds,Group II, drips, but

oes not urn cot on. Drippings burned cotton and ample extinguishes 65These data show that ZOR gives higher lmpact and heat t 30Sewndsdistortion temperatures than Cloran. BD Burn ng t me exceeds3%seeond; andddripsti B-ND Burning time exceeds 3 secon s an no ripping.EXAMPLE 11 TABLE VI Cnrln F-1 F-2 F-3 1 -4 F-5 F-e F-7 F8 F-9 ABS resin"100 100 100 100 100 100 100 100 100 zon 25 15 20 221 CNB 25 15 20 22.1sbioe 4 4 e 6 10.3 10.3 Impact notched izod R.T., V8 4. 7 3. 2 3. 0 3. 22. 8 2. 9 2. 5 2. 2 2. 1 Rockwell hardness, R 94 82 86 84 88 88 89 86 85Heat distortion temperature F.) 185 181 178 185 185 180 178 131 Theseresults show that ZOR gives higher impact and heat distortiontemperatures than CNB.

1 Roylar A-855 (trademark), a thermoplastic polyurethane product ofUniroyal, Inc.

The samples were prepared by milling the Roylar and r the flameretardant ZOR or Cloran, when used, at a temperature of 320 F. for 1minute and then gradually cooling for the next nine minutes. Finaltemperatures were about 270-280 F. The results given in Table VIIindicate that ZOR functions asan effective fire retardant additive forurethanes and has an added advantage over Cloran in that it reduces thedripping of the burning polymer. 1

EXAMPLE 13 TABLE VIII.-EVALUATION OF ZOR IN POLYPROPYLENE burn rateD-2863 (in./ oxygen Code Additive P.p.h. min.) index;

11-1. 15.4 S.E. 22.6 H-2- 20.6 S.E. 21.6 11-3- ZOR, SbzOa- 15.6 S.E.21.6 11-4--- "Cloran", SbaOa" 15.4 S.E. 21. 151-5 -do 15.6 S.E. 22.2

1 "Profax 6501" (trademark), a product oi Hercules, Inc., uustabilizedhomopolymer, nominal melt flow 4.0 (I1 at 230 0.). 7

These results indicate that "ZOR functions as a fire retardant forpolypropylene although olfering the advantages over Cloran.

Having thus described my invention, what I desire to protect by LettersPatent is:

1. A chemical compound having the structure 6-(1',4',5',6',7',7'-hexahalonorborn-5 en 2'-yl)-1,2,3,4,10,10-hexahalo-1,4,4a,5,6,7,8,8a-octahydro 1,415,8-dimethanonaphthalene.

2. The chemical compound 6-(1',4,5',6',7',7'-hexachloronorborn5'-en-2'-yl) 1,2,3,4,10,10 hexachloro- 1,4,4a,5,6,7,8, 8a-octahydro1,4:5,8 dimethanonaphthalene.

3. The method of making a chemical compound having the structure-6-(1',4',5',6',7',7'-hexahalonorborn-5'-en-2'- y1)-1,2,3,4,10,10hexahol 1,4,4a,5,6,7,8,8a octahydro- 1,4:5,8-dimethanonaphthalene whichcomprises reacting (A) 5-vinyl-2-norbornene with (B)hexahalocyclopentadiene, and recovering said compound from the reactionmixture. Y

4. The method of claim 3 wherein said hexahalocyclopentadiene ishexachlorocyclopentadiene.

5. The method of claim 3 wherein the molar ratio of reactant (B) toreactant (A) in said reacting step is at least 2:1.

6. The method of claim 5 wherein said reacting step is carried out byheating the reactants at a temperature of from 110 C. to 220 C. in aliquid organic solvent for said reactants.

claim and References Cited UNITED STATES PATENTS 8/1959 Fields 2611-1399/1960 Roberts 260--649R DANIEL D. HORWITZ, Primary Examiner I U.S. Cl.X.R. 260-], 45.75

